diff options
| author | Like Xu <likexu@tencent.com> | 2022-01-05 13:15:09 +0800 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2022-01-17 12:19:41 -0500 |
| commit | a21864486f7e220bd5938c6fb637613d9635739a (patch) | |
| tree | e5f73ec1ed5c738060b0835adbe2980128667550 /arch/x86/kvm/vmx | |
| parent | c862dcd199759d4a45e65dab47b03e3e8a144e3a (diff) | |
| download | linux-a21864486f7e220bd5938c6fb637613d9635739a.tar.bz2 | |
KVM: x86/pmu: Fix available_event_types check for REF_CPU_CYCLES event
According to CPUID 0x0A.EBX bit vector, the event [7] should be the
unrealized event "Topdown Slots" instead of the *kernel* generalized
common hardware event "REF_CPU_CYCLES", so we need to skip the cpuid
unavaliblity check in the intel_pmc_perf_hw_id() for the last
REF_CPU_CYCLES event and update the confusing comment.
If the event is marked as unavailable in the Intel guest CPUID
0AH.EBX leaf, we need to avoid any perf_event creation, whether
it's a gp or fixed counter. To distinguish whether it is a rejected
event or an event that needs to be programmed with PERF_TYPE_RAW type,
a new special returned value of "PERF_COUNT_HW_MAX + 1" is introduced.
Fixes: 62079d8a43128 ("KVM: PMU: add proper support for fixed counter 2")
Signed-off-by: Like Xu <likexu@tencent.com>
Message-Id: <20220105051509.69437-1-likexu@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86/kvm/vmx')
| -rw-r--r-- | arch/x86/kvm/vmx/pmu_intel.c | 18 |
1 files changed, 12 insertions, 6 deletions
diff --git a/arch/x86/kvm/vmx/pmu_intel.c b/arch/x86/kvm/vmx/pmu_intel.c index 5e0ac57d6d1b..ffccfd9823c0 100644 --- a/arch/x86/kvm/vmx/pmu_intel.c +++ b/arch/x86/kvm/vmx/pmu_intel.c @@ -21,7 +21,6 @@ #define MSR_PMC_FULL_WIDTH_BIT (MSR_IA32_PMC0 - MSR_IA32_PERFCTR0) static struct kvm_event_hw_type_mapping intel_arch_events[] = { - /* Index must match CPUID 0x0A.EBX bit vector */ [0] = { 0x3c, 0x00, PERF_COUNT_HW_CPU_CYCLES }, [1] = { 0xc0, 0x00, PERF_COUNT_HW_INSTRUCTIONS }, [2] = { 0x3c, 0x01, PERF_COUNT_HW_BUS_CYCLES }, @@ -29,6 +28,7 @@ static struct kvm_event_hw_type_mapping intel_arch_events[] = { [4] = { 0x2e, 0x41, PERF_COUNT_HW_CACHE_MISSES }, [5] = { 0xc4, 0x00, PERF_COUNT_HW_BRANCH_INSTRUCTIONS }, [6] = { 0xc5, 0x00, PERF_COUNT_HW_BRANCH_MISSES }, + /* The above index must match CPUID 0x0A.EBX bit vector */ [7] = { 0x00, 0x03, PERF_COUNT_HW_REF_CPU_CYCLES }, }; @@ -75,11 +75,17 @@ static unsigned int intel_pmc_perf_hw_id(struct kvm_pmc *pmc) u8 unit_mask = (pmc->eventsel & ARCH_PERFMON_EVENTSEL_UMASK) >> 8; int i; - for (i = 0; i < ARRAY_SIZE(intel_arch_events); i++) - if (intel_arch_events[i].eventsel == event_select && - intel_arch_events[i].unit_mask == unit_mask && - (pmc_is_fixed(pmc) || pmu->available_event_types & (1 << i))) - break; + for (i = 0; i < ARRAY_SIZE(intel_arch_events); i++) { + if (intel_arch_events[i].eventsel != event_select || + intel_arch_events[i].unit_mask != unit_mask) + continue; + + /* disable event that reported as not present by cpuid */ + if ((i < 7) && !(pmu->available_event_types & (1 << i))) + return PERF_COUNT_HW_MAX + 1; + + break; + } if (i == ARRAY_SIZE(intel_arch_events)) return PERF_COUNT_HW_MAX; |